As it is known in the art, Storage Area Network (SAN)s are often used by various entities to consolidate or backup data. The consolidation of storage is important from both cost-savings and data security standpoints. A centralized data storage location removes the need for expensive storage devices to be provided at each user locale; rather storage capacity at the data center can be shared by a number of different servers at physically different locations. The data center is often physically distant from the application servers and associated users, and can be used to provide redundant storage for application data to ensure that desired levels of data security and disaster recovery can be maintained. The data center includes one or more storage systems, where the storage system could be RAID, tape backup, tape library, CD-ROM library, or JBOD (Just a Bunch of Disks).
FIG. 1 illustrates a typical application environment which includes a number of users 2 coupled via a WAN such as IP network 4 to a number of application servers 6. The application servers are coupled by a Fibre Channel network 8 to a data center 9 which may include one or more types of Fibre Channel storage devices. Fibre Channel is a serial data transfer architecture developed by a consortium of computer and mass storage device manufacturers, and is the preferred network implementation for SANs.
To deliver the required behavior, the application servers 6 generally include functionality to support the WAN protocol (for communication with the users), the Fibre Channel protocol (for communication with the data centers), and potentially LAN functionality to permit communication with the local area network of servers. Each of the networks must be managed, and management may be by different' entities. Thus the expense of supporting and managing the multiple networks is substantial. In addition, the solution allows the network owner to reapply valuable assets and capacity to deliver added value. It would be desirable to identify a network architecture that would permit network capacity to be shared among users in a metro network while enabling desired levels of performance and disaster recovery to be maintained.